Hydrocarbyl amine substituted propionic ester and motor fuel composition containing same

ABSTRACT

Hydrocarbylamine substituted propionic esters represented by the formula: RR&#39;&#39;NCH2CH2COOR&#39;&#39;&#39;&#39; in which R is an aliphatic hydrocarbon radical having from 12 to 22 carbon atoms, R&#39;&#39; is hydrogen or a lower alkyl radical having from 1 to 2 carbon atoms and R&#39;&#39;&#39;&#39; is a hydrocarbon radical having from about 8 to 22 carbon atoms, and a motor fuel composition containing said esters.

COMPOSITION CONTAINING SAME William M. Cummings, Fishkill, N.Y.

Assignee: Texaco Inc., New York, NY.

Filed: Dec. 18, 1974 Appl. No.: 533,909

Inventor:

References Cited UNITED STATES PATENTS United States Patent 1 1 1 3, 8

Cummings 5} Dec. 16, 1975 HYDROCARBYL AMlNE SUBSTITUTED 3,260,745 7/1966Andress, Jr. et al 44/71 PROPIONlC ESTER AND MOTOR FUEL 3,429,817 2/1969Furcy et al 44/58 3,758,555 9/1973 Winkelmann 260/482 R PrimaryExaminer-Daniel E. Wyman Assistant Examiner-Mrs. Y. Harris-SmithAttorney, Agent, or FirmT. H. Whaley; C. G. Ries; James J. O'Loughlin[57] ABSTRACT Hydrocarbylamine substituted propionic esters representedby the formula:

RR'NCH,CH,COOR" 6 Claims, No Drawings HYDROCARBYL AMINE SUBSTITUTEDPROPIONIC ESTER AND MOTOR FUEL COMPOSITION CONTAINING SAME BACKGROUND OFTHE INVENTION Field of the Invention Modern internal combustion enginedesign is undergoing important changes to meet new Federal standardsconcerning engine exhaust gas emissions. A major change in engine designrecently adopted is the feeding of blow-by gases from the crankcase zoneof the engine into the intake air supply of the carburetor rather thanventing these gases to the atmosphere as in the past. A further changebeing adopted involves the recycling of a part of the exhaust gases tothe combustion zone of the engine in order to effect a more completecombustion and to further reduce objectionable exhaust emissions. Therecycled exhaust gases contain substantial amounts of deposit-formingsubstances which promote the formation of deposits in and around thethrottle plate area of the carburetor. These deposits have the effect ofrestricting the flow of air through the carburetor at idle and at lowspeeds so that an over-rich fuel mixture results. This conditionproduces rough engine idling and stalling and serves to increase theharmful exhaust emissions which the engine design changes were intendedto overcome.

Modern gasoline compositions are very highly refined products. Despitethis they contain minor amount of impurities which can promote corrosionduring the period that the bulk fuel is being transported and stored andalso in the fuel tank, fuel lines and carburetor of the motor vehicle.An acceptable motor fuel must contain an effective and compatibleinhibitor to inhibit or prevent corrosion during transport and prior toits use in the engine.

SUMMARY OF THE INVENTION A class of hydrocarbyl amine substituted estersof propionic acid has been discovered which are effective as detergentsand corrosion inhibitors when employed in a liquid hydrocarbon fuel foran internal combustion engine. These compounds, which are characterizedby having two relatively long hydrocarbyl groups namely ahydrocarbylamine substituent and an ester substituent. appear to beunique in their carburetor detergency and corrosion inhibitingproperties.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The hydrocarbylarninesubstituted ester of propionic acid is represented by the formula:

RR'NCHJI'HZCOOR" in which R' is an alkyl radical having from about 8 to12 carbon atoms.

The prescribed hydrocarylaminc substituted ester of propionic acid isprepared by reacting approximately equal mole amounts of an aliphaticamine. acrylic acid and an alcohol or hydroxy compound. In general. thereaction is conducted in two steps. In the first step equivalent amountsof the alcohol and acrylic acid are combined in a suitable hydrocarbonor inert solvent. such as xylene and heated to reflux temperature in thepresence of an effective esterification catalyst such as p-toluenesulphonic acid. This reaction is continued until the stoichimetricalamount of water has been collected. In the second step, an equivalentamount of a hydrocarbylamine is added and the reaction temperature heldat a temperature of about l20C These reaction conditions are continuedfor sufficient time to permit the addition of the hydrocarbylamine tothe propionic acid ester. The solvent is then removed by distillationfor recovery of the desired product.

Examples 1 to 4 below illustrate the preparation of hydrocarbylacrylates which is the first step in the preparation of hydrocarbylaminoalkyl propionate.

EXAMPLE l Dodecylphenylacrylate To 256g of dodecylphenol in 1000 ml ofxylene is added l44 g acrylic acid (AA), 20 g hydroquinone (HQ) and l5.0g p-tolunesulfonic acid (PTSA). This mixture is heated at reflux C) forl l hours while the water of reaction is collected (approximately 20ml).The reaction mixture is cooled. and the xylene removed under reducedpressure to give approximately 400 g dodecyl phenylacrylate. Theanalytical data for this acrylate are shown below:

C2022 N-Alkyl Acrylate To 300 g of C2042 n alkyl alcohol in 300 mlxylene is added 72g AA, 0.3g HO and 30g PTSA. This reaction mixture isheated for 12 hours at reflux (approximately 140) while the water ofreaction is collected (approximately l7.5ml). The reaction mixture iscooled, and the xylene removed under reduced pressure to give 329g C2042n-alkylacrylate. The analytical data for this acrylate is shown below:

Neut.

Prep. No. SAP No. No.

lsodecyl Acrylate To 157g isodecyl alcohol in 200ml xylene is added 117g AA, 1.0g HQ and 2.00 PTSA. The reaction mixture is heated for 2 hrs.at reflux (approximately 140C) while the water of reaction is collected17ml). The reaction mixture is cooled and the xylene removed underreduced pressure to give 250g isodecyl acrylate. The analytical data forthis acrylate is shown below.

Neut. Prep. No. SAP No. No.

EXAMPLE 4 Phenoxy (Polyethoxy) Ethyl Acrylate To 58.6 g of phenoxy(polyethoxy) ethanol* in 60 ml xylene is added 14.4 g AA, 0.2g HO and gPTSA. This mixture is heated to the reflux point (approximately 140C)for 5 hrs. while the water of reaction is collected (approximately3.0ml). The reaction mixture is cooled and the xylene removed to give65g of penoxy (polyethoxy) ethyl acrylate. *Tritonyl 45 is a phenoxy(polyethoxykthanol made by Rohm and Haas containing 4-5 ethoxy groups.

Neut. Prep. No. SAP No. No.

The following examples illustrate the second step in the process forproducing hydrocarbylamino alkyl propionates by reacting ahydrocarbylamine with the alkyl acrylate of step 1.

EXAMPLE 5 2(Tallowamine) Dodecyl Phenyl Propionate To 622g dodecylphenyl acrylate in 100 ml xylene is added 54g tallowamine (Armeen T) andthis mixture is heated at 120C for 3 hours. The xylene is removedEXAMPLE 6 2(C sec. Alkyl Amino) C2042 N-Alkyl Propionate To g of Cn-alkyl acrylate is added 46g C secondary alkyl amine (Armeen L-15) andthis mixture heated for 4 hrs. at 150C. The analysis and test resultsfor this material are shown below:

Analysis Prep. No. [6 Prep. No. 17

TBN 62 78.4

SAP No. 44 30.9

Mole Wt. 635

EXAMPLE 7 2(C,;,. Secondary Alkyl Amino) lsodecyl ropionate To 38.8isodecyl acrylate is added 67g C secondary alkyl amine (Armeen L-l5) andthis mixture is heated for l hr. at C. The analysis and test results forthis material are shown below:

Analysis Prep. No. 18

TBN 102.8 SAP N0. 54.9

EXAMPLE 8 2(Tallowamino) Phenoxy (Polyethoxy) Ethyl Propionate To 44.8gof phenoxy (polyethoxy) ethyl acrylate in 70ml xylene is added 34.0tallowamine (Armeen T) and this mixture is heated at 120C for 4 hours.The xylene is removed under reduced pressure. The analysis and testresults for this 2(tallowamino) phenoxy (polyethoxy) ethyl propionate isgiven below:

Analysis Run No. 19

TEN 54.9 SAP No. 500 Neut. No. [2.8

The following table lists representative examples of hydrocarbyl aminesubstituted propionic esters of the invention:

2-(C 15.2 secondary alkyl amine) isodecyl propionate 2-(C 12.14secondary alkyl amine) isodecyl propionate 2-(cocoamine) isodecylpropionate 2-(tallowamino) isodecyl propionate 2-(methyl C1540 secondaryalkyl) amino isodecyl 55 propionate v f g i r fi z i gi g s ziz z gxg2-(C 15.20 secondary alkyl) dodecyl phenyl propionate i i an Z-(Csecondary alkyl dodecyl phenyl propionate) OW 2-(cocoamine) dodecylphenyl propionate Analysis Prep. No. 1] Prep. No. 1] Prep. No. 14 Prep.No. 15

TBN-ST-JIZ 45.6 46.7 45.6 43.9 SAP No 41.x 49.: 6] 7 18.5 ck 2w Neut.No. Aux 43.5 49.5 1 421 UK 21.8 TAN 315 43.9 OH .22 119 I3) 136 "i N1.33 2.3 no solvent 2.4 Sp. Gr. 0 948 used in the reaction2-(tallowamine) dodecyl phenyl propionate 2-(methyl C secondary alkylamino) dodecylphenyl propionate 2-(C secondary alkyl) C2042 n-alkylpropionate 2-(C, secondary alkyl) C2042 n-alkyl propionateZ-(cocoamine)-C -n-alkyl propionate 2-(tallowamino)-C -n-alkylpropionate 2-(methyl C secondary alkyl amino) O n-alkyl propionate Z-(Csecondary alkyl amino) hexadecyl propionate 2-(C secondary alkylamino)hexadecyl propionate 2-(cocoamino) hexadecyl propionate 2-(tallowamino)hexadecyl propionate 2-(methyl C secondary alkyl) hexadecyl propiomateThe prescribed hydrocarbylamine ester of the invention is employed in agasoline motor fuel composition in a concentration to provide botheHective carburetor detergency and corrosion inhibiting properties. Ingeneral, an effective concentration of the additive ranges from about0.001 to 0.l weight percent with a preferred concentration ranging fromabout 0.01 to 0.075 weight percent. The limits of the preferred rangecorrespond respectively to about 25 and 200 PTB (pounds of additive per1000 barrels of gasoline).

Any gasoline suitable for a spark-ignited, internal combustion enginecan be used in the practice of this invention. In general, the base fuelwill consist of a mixture of hydrocarbons in the gasoline boiling range,i.e., boiling from about 75 to 450F. The hydrocarbon components canconsist of paraffinic, naphthenic, aromatic and olefinic hydrocarbons.This gasoline can be obtained naturally or it can be produced by thermalor catalytic cracking and/or reforming of petroleum hydrocarbons. Thebase fuel will generally have a Research Octane Number above 80 and upto 102 with the preferred range being from about 85 to 100.

The prescribed hydrocarbylamine ester additive of the invention wastested for its corrosion inhibiting properties in gasoline in theColonial Pipeline Rust Test described below:

COLONIAL PIPELINE RUST TEST A steel spindle. 3 3/ l6 inches long and /2inch wide, made from ASTM D-665-60 steel polished with Crystal Bay fineemery paper, is used in the Colonial Pipeline Rust Test. The spindle isplaced in a 400cc beaker with 30000 of fuel sample, which is maintainedat 100F. for one-half hour. Then cc of distilled water is added. Thebeaker and contents are kept at l0OF. for 3 /2 hours. The spindlethereafter visually inspected and the percentage of rusted surface areais estimated.

The Base Fuel designated Base Fuel A, employed in the following exampleswas a premium grade gasoline having a Research Octane Number of about100 and contained 3 cc. of tetraethyl lead per gallon. This gasolineconsisted of about 25 percent aromatic hydrocarbons. [0 percent olefinichydrocarbons and 65 percent paraffinic hydrocarbons and boiled in therange from about 90F to 380F.

The results of this test are set forth in Table I belowv "PTB Pounds ofadditive per I000 gallons f gasoline.

CHEVROLET CARBURETOR DETERGENCY TEST This test is run on a Chevrolet V-8engine mounted on a test stand using a modified four-barrel carburetor.The two secondary barrels of the carburetor are sealed and the feed toeach of the primary barrels arranged so that separate fuels can be runin each barrel simultaneously. The primary carburetor barrels are alsomodified so that they have removable aluminum inserts in the throttleplate area in order that deposits formed on the inserts in this area canbe conveniently weighed.

In the procedure designed to determine the effectiveness of an additivefuel to remove preformed deposits in the carburetor, the engine is runfor a period of time, usually 24 to 48 hours, using the base fuel as thefeed to both barrels with engine blow-by circulated to the air inlet ofthe carburetor. The weight of the deposits on both sleeves is determinedand recorded. The engine is then cycled for 24 additional hours with areference fuel being fed to one barrel, additive fuel to the other, andno blow-by to the carburetor air inlet. The reference fuel contains 15PTB of a carburetor detergent. The inserts are then removed from thecarburetor and weighed to determine the difference between theperformance of the additive and non-additive fuels in removing thepreformed deposits. After the aluminum inserts are cleaned, they arereplaced in the carburetor and the process repeated with the fuelsreversed in the carburetor to minimize differences in fuel distributionand barrel construction. The effectiveness of the additive fuel isexpressed as the difference (A) between deposit removed by the additivefuel and the deposit removed by base fuel. When A is positive, theadditive fuel has removed more deposit than the reference fuel.

The motor fuel used as a standard for comparison purposes in this testis a commercial high octane premium gasoline containing a highlyeffective carburetor detergent. The fuel composition representative ofthe invention consisted of Base Fuel A described above containing theindicated amounts of the additive of the invention. The results of thistest are reported as the difference in carburetor deposits removed bythe additive containing gasoline of the invention in comparison to thecommercial premium detergent gasoline.

The results of the Chevrolet Carburetor Detergency Test are set forth inTable II below.

The foregoing tests demonstrate the outstanding corrosion inhibiting andimproved carburetor detergency properties of the fuel composition of theinvention This novel fuel composition is particularly suitable formaintaining the cleanliness and low exhaust emission from a moderninternal combustion gasoline engine I claim:

1. A motor fuel composition comprising a mixture of hydrocarbons in thegasoline boiling range containing from about 0.00] to 0.1 wt percent ofa hydrocarbyla mine ester represented by the formula:

RRNCH. .CH2COOR" in which R is an aliphatic hydrocarbon radical havingfrom about 12 to 22 carbon atoms R' is hydrogen or a lower aliphatichydrocarbon radical having from 1 to 2 carbon atoms and R" ishydrocarbon radical having from 8 to 22 carbon atoms.

2. A motor fuel composition according to claim 1 in which R is analiphatic hydrocarbon radical having from 16 to IR carbom atoms, R ishydrogen and R" is an alkyl substituted phenyl radical having from 14 to20 carbon atoms.

3. A motor fuel composition according to claim 1 in which saidhydrocarbylamine ester is 2-(tallowamin0) dodecylphenyl propionate.

4. A motor fuel composition according to claim 1 in which saidhydrocarbylaminc ester is Z-(C sec. alkylamino) C2042 n-alkylpropionate.

5. A motor fuel composition according to claim I in which saidhydrocarbylamine ester is 2-(C secondary alkylamino) isodecylpropionate.

6. A motor fuel composition according to claim 1 in which saidhydrocarbylamine ester is 2(tallowamino) phenoxy (polyethoxy) 4-5 ethylpropionate.

1. A MOTOR FUEL COMPOSITION COMPRISING A MIXTURE OF HYDROCARBONS IN THEGASOLINE BOILING RANGE CONTAINING FROM ABOUT 0.001 TO 0.1 WT. PERCENT OFA HYDROCARBYLAMINE ESTER REPRESENTED BY THE FORMULA:
 2. A motor fuelcomposition according to claim 1 in which R is an aliphatic hydrocarbonradical having from 16 to 18 carbom atoms, R'' is hydrogen and R'''' isan alkyl substituted phenyl radical having from 14 to 20 carbon atoms.3. A motor fuel composition according to claim 1 in which saidhydrocarbylamine ester is 2-(tallowamino) dodecylphenyl propionate.
 4. Amotor fuel composition according to claim 1 in which saidhydrocarbylamine ester is 2-(C15-20 sec. alkylamino) C20-22 n-alkylpropionate.
 5. A motor fuel composition accordIng to claim 1 in whichsaid hydrocarbylamine ester is 2-(C15-20 secondary alkylamino) isodecylpropionate.
 6. A motor fuel composition according to claim 1 in whichsaid hydrocarbylamine ester is 2(tallowamino) phenoxy (polyethoxy) 4-5ethyl propionate.